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I think they powder coat. The process itself is great. There are several choices for material, also. I'm just not sure it's best for this particular application.
Colored anodized metal can fade for sure, and like powder coating, the skill of the anodized and process will determine the success. Proper annodizing isc quite durable, but the main advantage here is that it won't change the dimensions of the part, or otherwise cause problems with edges and corners.
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The best stuff I ever used was One Coat brand clear plastic spray. It was my sculpture instructor's go-to for clear-coating aluminum. Their paint was pretty good too. Back in the 1980s we used to get it at Roses Dept. stores for $1 a can. I have no idea if they still carry it. They sold it as the store brand but later I also saw it other places. Tried looking it up online. No dice.
"Live like no one else, so later, you can LIVE LIKE NO ONE ELSE!"
- Dave Ramsey
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Maybe I'm not understanding the original post, but if the aluminum is inlayed, I don't think all these suggestions of powder-coating or anodizing or special aluminum-only finishes is going to be a viable option, as what I think he is looking for is a homogeneous finish that can cover the wood and metal in one continuous application. A big question I have is what will the surface finish of the aluminum be? Will it be bright polished, or scuffed to a uniform matte finish? Either finish can be achieved with inlay; it's just a function of how fine a grit of sandpaper and/or buffing you use. A typical 220/320 grit finish on wood will yield a fairly dull matte finish on the aluminum; 800 grit gets you to the beginning of what might be described as a shiny polish.
I too am interested in this subject, as I have a few designs in my head that will need a similar finish and I have not tried this yet, although I have polished a LOT of aluminum in my life!
K
Member
Kevin raises some interesting considerations.Originally Posted by Kevin Nathanson
There is no reason that you cannot pre-finish your aluminum parts then inlay your wooden parts, particularly if you're going to use mechanical fasteners to hold the inlay.
If you are going to go for a polished or any kind of bright metallic look, you'll need a surface coating to maintain that. On its own, exposed, aluminum develops a dull blackish-grey surface oxidation that can be quite nice if it fits with your design. Most alu. alloys will be a dull battleship grey when sandblasted.
The first piece below with the vertical rods was sandblasted, the I masked off the center tree structure and spray-painted the exposed areas with black Roses One Coat then knocked off the excess paint and polished the high spots with a wire-wheel and coated it with the Roses One Coat clear plastic. The photo was taken about a year later.
The second piece went through the same process, but the entire piece was painted and wire-wheeled, and there's no top coat. The photo for it was about 6 months later.
Both of those sold, so I have no idea how they look now, but I've recently seen pieces that I helped my mentor create in the mid-1980s and they look pretty much the same as when he finished them.
The stump piece was done basically the same way, but on the geometric pieces I focused the wire-wheel on the edges so more black paint stayed on the open areas. The stump and roots were first coated with black, then multiple colors at random. Then the whole thing was wire-wheeled, and there's no topcoat. The photo was about a year later, but that thing sat in my parents back yard for 7-8 years, and except for debris it looked essentially the same when I cut it up to melt it down.
miniature_ii.jpg solid_alu.jpg sittin_stump.jpg
"Live like no one else, so later, you can LIVE LIKE NO ONE ELSE!"
- Dave Ramsey
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You, and the rest of us, are not playing in their league in terms of processes, chemistry, and supplier R&D. And the proprietary locks on that type of knowledge are beyond belief.
I spent a number of years in the manufacturing end of a company that manufactured high-performance aluminum windows [not only fixed, but operating windows and patio doors] for big-time architectural projects. Battery Park in lower Manhattan was one of ours - many different colors - and there were many other projects. This goes back to the late 80's + early 90's.
We did not clear-coat, but the process issues are the same. A coating will not stick to aluminum. It will stick to a substrate. But, the substrate will not adhere to aluminum, either. So - first station in the paint line was wash off the environment trash and dirt, then an etch, then rinse, then rinse again, then substrate application [chrome-based], then rinse, then rinse again, then paint, then paint, then cook. And - a big operation to process the chrome overspray and rinses, to convert it to inert non-haz material. Understand - this paint line handled 30' long extrusions, hung 8" OC, moving at maybe 30 LFPM.
If I was going for this appearance, I would be looking for an anodizing operation, to be honest. They have the gear, they have the haz mat handling procedures and equipment, and they have the experience. I would also have it bent / formed to its final shape before I sent it out.
When I started woodworking, I didn't know squat. I have progressed in 30 years - now I do know squat.
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I was curious as to what others do with aluminum so I visited some of the auto/ hot rod forums as well as motorcycle forums. Not exactly a scientific study, but here is what I noticed.
From what I have read they mostly recommend not applying any clear finish to aluminum. One poster mentioned "you are just looking for trouble". It appears the next most common recommendation was clear anodizing.
[OP]
Contributor
Fellows,
I'm actually overwhelmed by the responses this thread stirred up. I very much appreciate the comments and the knowledge that you have given me. I'll try to post a few pictures in a day or so of what I'm doing. Picture a table top that is 8ft long, 45 inches wide and 2.5 inches thick figured maple. Now the top is in two pieces, both are 22" wide. The extra inch that makes it 45 inches is a 1" gap between the two tables. This gap is a design feature that carries throughout the legs and the benches. The slabs are joined by the aluminum bars that I originally asked about. Each slab/leg/bench has this feature. There are pairs of slots cut into the slabs that match each other. The aluminum is the structual member that joins the slabs. The table for instance will have 8 bars that are in pairs of two 1" apart and 20 inches between the pairs to hold the table top together.
Anodizing is problably more realistic for the reason that it adds nothing to the dimensions. There is always a problem correct. Well I was hoping to epoxy these 2.5"x7" pieces into the top to hold it together and then finish everything at once so the top of the aluminum and the wood itself were sanded to level at one time. Then spray the finish on and do the taping if needed to specific parts. I'd download some pictures but my brand new iphone plus is not downloading to my computer for some reason. The anodizing would not effect the adhesiveness of the epoxy but other top coatings would if I were to finish the aluminum first and then try to glue then into their positions. I was hoping to etch them somehow and then tape off the areas to be finished and glue them into place, then remove the tape and spray the entire top or bench depending.
I'm thinking if I anodize them I will not have them perfectly at the level of the wood since I'll not be able to sand over top of them. When I post again I'll try to get my other camera out to leave a few pictures of what I'm doing. I'm sure something will work somehow.....
This afternoon I was talking to a friend that is involved with racing and he told me he believes that the product they use on his aluminum body top fuel car is called Aluma Bond. He's under the belief that this is a coating that is applied before painting. Now he was telling me that years ago they used this under lacquer all the time. I'll have to check out the local body shop...right? cars are aluminum now.
thank you
Ben
Last edited by Ben Abate; 11-24-2014 at 2:55 PM.
[OP]
Contributor
Kevin you are correct in what you were thinking. I know I did not explain myself very well with my original post because i was not expecting such a great response I guess. The parts are really not inlays, they are structual aluminum bars that span the two table tops in order to keep them together in parallel to each other. There are structual members under the table that are hidden to do the actual real support. I was hoping to expoxy these in place with great accuracy and then do a final sanding before finishing.
Ben
Contributor
If it works out, it will be a cool look, but I'll be very honest that I wonder about the expansion at the joint, especially long term if it will actually stay flush with the wood. Also, reliably bonding aluminum is a whole other can of worms, similar to the finishing can of worms. I think you've taken on a very difficult project, and you will have to do everything exactly right, and in exactly the right order, to pull it off. That's assuming you ignore potential wood expansion/contraction problems later on. I'm not saying it's impossible. Just that you've inadvertently chosen a material that can sometimes be difficult to incorporate into projects without some jumping through hoops and careful planning.
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Nonsense. Aluminum is coated hundreds of thousands of time each year by all sorts of DIY'ers and they all have great success doing it.From what I have read they mostly recommend not applying any clear finish to aluminum. One poster mentioned "you are just looking for trouble"
The ones that don't, short cut the prep part and/or use the wrong product.
There's no voodoo or black magic involved, just proper surface prep and proper product selection.
As I mentioned above, I sold the devil out of the XIM product from 1966 through 1987 and had zero complaints about it.
Simply call these people on the phone- (XIM tech support)
1.800.262.8469 x120
"Life is what happens to you while you're busy making other plans." - John Lennon
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How are you going to prep it buried in wood?
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If I read the above correctly, the pieces can be prepped and primed before they go into place.
"Life is what happens to you while you're busy making other plans." - John Lennon
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